Plugging in

Unplugging Is Uncool, But So Is Hogging The Power

It’s a tricky problem. You need to charge up, but there’s someone else parked at the charging station and they appear to have been there a while. They’ve finished charging and you need to get on your way.

Unplug, or find somewhere else to charge. Just what do you do?

Of course, it never used to be a problem, because very few people took their EVs beyond the safety limits of a single-charge. But as EV sales slowly rise and charging networks become more reliable, we’re bumping into more and more people at public charging stations. Sometimes we even have to queue to charge, and sometimes we arrive to find a fully charged car, still connected to the station, its owner nowhere to be seen.

While we think this falls into the category of ‘nice problem to have’, it is still a problem. Unique to electric cars — when did you last see someone park at a petrol station and then walk off? — it presents some tough questions.

How do you determine who needs the charger more? Who gets to say who can be unplugged or not? And can you unplug a car if it hasn’t finished charging but you’re late for your 4pm appointment?

Enter reader Jason Wallace, who reached out to us on twitter with with just this kind of problem. Wallace says he sees the same car plugged into a public charging station for hours and hours at a time, well beyond the length of time needed to charge it up. What could he do, he asks, if he drove up needing a charge?



In trying to codify our response, we had a tough time finding a catch-all response.


Would you unplug?

Would you unplug?

One solution would be to just unplug the offending car. Unlike the state of California where state legislature makes it illegal to be parked at a charging station without being plugged in – thus making ‘charger sharing’ illegal, there’s nothing to theoretically stop you from unplugging someone else’s car in the UK. Except maybe politeness.

However, as we have to supply our own cable to use with charging stations on the street in the UK, the Transport Evolved team can’t think of anything that would be ruder in the electric car world than to unplug someone else’s car then use their cable to charge up yours.

Newer cars eliminate the problem altogether, since they usually lock the charge cable onto the car’s charge inlet and make it impossible to unplug the cable from the locked car.

If you’re using a Type 2 (Mennekes) charging station – the EU standard – the other end of the charging cable is locked into the charger while power is being supplied anyway, making it impossible to unplug a charging car if both ends of the cable are locked.

Since the lock on the charging station stays active while power is being delivered to the car, when charging ends the cable lock should disengage, allowing someone else to come along, unplug the first car and then plug their own car in.

The issue with this is that the car needs to have finished charging and the charging station needs to be programmed to know that it is okay to release the cable without a swipe of the ‘Smart’ card carried by the initial user in this situation. Smart RFID cards, in this situation, could potentially ‘reserve’ a charging station for one car even after it is fully charged until the owner returns.

The EV Hierarchy of Needs

What happens if you get to a charging station and the other driver is there? Then what?

Who needs to charge more?

Who needs to charge more?

There is a unwritten set of recommendations when it comes to this – although Chevrolet did just write some of them down to help new Spark EV drivers. The recommendations are as follows:

  • Pure electric cars trump plug-in hybrids/range-extended hybrids.The argument being they have another means of propulsion.
  • A pure-EV with enough range to move on to the next charger should do if the other car wouldn’t be able to make it.
  • If neither vehicle can make it to the next charging station, priority comes down to need. Now this could be how much or little charge is needed, one person needing to be somewhere at a certain time or any other factor.


To return to Jason’s query, we’re afraid there’s not a lot he can do. It’s likely the charging station is waiting for the owner to return and swipe their RFID card before releasing the charging cable.

The best to hope for would be that the owner has a note in the window with contact details. That way people who need a charge can get in touch and – hopefully – get access to the charger.

That’s why we recommend all plug-in drivers to leave a note in the window of your car with contact details on it if you’re in a location with just one charging station. Allow people to get in contact. You never know when you may be the one needing the charge.

What would you do in Jason’s situation? Do you think anything needs to be added to the EV Hierarchy of Needs? Does the size of the pure-EV’s battery matter? Let us know in the comments below.


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  • johnbreakwell

    Sounds like a potential cause of road rage as the demand increases. Interesting problem.

  • Jeffery Lay

    I disagree that the car and charging point should unlock the cable when charging is complete. This would leave an expensive cable that could be stolen by any passing opportunist. You might wonder who wants a 5m cable which really has only one application, but we live in a country where people are ripping emergency telephone lines out of the ground in order to sell the copper they contain. Tragic but true.nnGranted this cable doesn’t cost as much as the ‘soap-on-a-rope’ portable EVSE, but the cheapest Type 2 to J1772 cable I’ve seen around still costs about u00a3200u2026 and so far, insurers seem to think that even a cable provided with the car is not “part of” the car, and as such it’s not insured.

    • Chris Brooks

      Agreed the loss of a cable is bad, however going forward the cable should stay locked to the car until owner returns.nSo when charging is complete the charging point releases the cable so it could be unplugged if needed but is still firmly attached to the car.nnnTaking this a step further, perhaps the charge point should unlock after a set time regardless of charge state, If the cable is not unplugged then then charging continues.nJust need to solve the problem of taking out a cable that is ‘live’. ‘Set-time’ would be based on both time and KWh.

      • Mark Chatterley

        This was my intention in the article. The idea of the cable staying locked to the car but being removable from the charging station seems like the best way forward. The current issue with that is ‘charging sessions’ are determined – in many cases – by swiping of RFID cards.

        • Chris Brooks

          As I said going forward. It is something that needs to be planned and started now to prevent upset and set backs of EV adoption.nIf people cannot charge there may just as well be no charge points. (Not that many are any use to me in a Twizy).nnRFID Cards could still be used to start a ‘measured or timed’ charge. As long as the cable is locked to the car (add to central locking) then the Charge Point can release the cable lock at it’s end when time limit etc is reached. If there was still being current drawn then the session could stay until point was needed or owner came back. nnnnIf session still in play then RFID card would be required to release cable as now.nIf session is complete (limted reached) then any RFID card could unlock the cable.nnnNeeds some new logic at charge points. Also an agreed limit to the time or power supplied before cable release logic works.

  • David Khoo

    I think the future is not to far off when there’s;nnna) common usage of autonomous vehicles.nb) common usage of high speed wireless charging clever ways to sort charging priority using charge state, driver destination and departure times, and a fee for urgency consideration, similar to option town (plane seat upgrades), but where vehicles can accept a small tip for letting another vehicle cut in line, or trade it for priority at a later date.nnnMost of the parking bays would be normal bays, with WiFi data connections available and markings that allow autonomous vehicles to easily find and access the high speed wireless charging bays, when the facility has allocated them charging time based on an algorithm.nnnWhen a vehicle is charged, it can park itself in a normal bay, freeing another autonomous vehicle to park and charge up, and so on till all the vehicles are charged.

  • Chris

    Well, here in California, the rules are a little different than they are made out to be in this article, of course it is possible they changed since this was written.

    You cannot get a ticket for parking at a charging station and not plugging in, unless the signage at the stations states otherwise.

    That being said, the business CAN tow vehicle that are not plugged in if they have signage letting them know this.

    The reality is very few businesses do this, but most take a common sense approach and check regularly, thus they know if a vehicle was charging earlier in the day, but someone unplugged them to plug in.

    Of course here in California we do not generally provide our own cables at public chargers, so I see no issue with unplugging someone who is clearly fully charged. If you are concerned they might get a ticket or be towed, leave a notice on their windshield saying they were indeed charging and you unplugged them in order to plug in, so please do not ticket or tow, as you are sharing the plug since they were fully charged.

    Additionally, we now have charging stations that charge occupancy fees if you remain plugged in after being fully charged, at these locations unplugging someone who is fully charged may actually be beneficial to them as well.

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